Safety switch for covers of washing machines



March 1951 H. B. WALLIS ET AL 2,544,867

SAFETY SWITCH FOR COVERS OF WASHING MACHINES Filed Nov. 4, 1944 2 Sheets-Sheet 1 FIG. I

I VENTORS mzlq 5Z4 414% W March 13, 1951 H. B. WALLIS ET AL 2,544,867

SAFETY SWITCH FOR COVERS 0F WASHING MACHINES Filed Nov. 4, 1944 2 Sheets-Sheet 2 I I I [a [4 Patented Mar. 13, 1951 UNITED STATES PATENT OFFICE' SAFETY SWITCH FOR COVERS OF WASHING MACHINES Harold B. Wallis and Duane Neal, Qaytqn, Ohio, assign'orsto General Motors Corporation,

Dayton, Ohio, a corporation of pelaware Application November 4, 1944,;Serial No, 561,857 9 Claims. (01. (58-12) invention relates to washing machine, and more particularly to the automatic control of such washing machines.

An object of this invention is to provide a centrifugal washing machine with a control such that when the access door is opened during the centrifugal action all operations are automati cally stopped. Also should the door remain open when centrifugal operation is reached, all'operations are automatically stopped.

Further objects and advantages of the present invention will be ap'parent'from the following description, reference being had to the accom? panyin'g drawings, where n a'preferred form of the present invention is clearly shown.

In' the drawingsi Fig.1 is a diagrammatic representation of the washing machine and its control Fig. 2 is a diagrammatic representation of the timer control, in combination with the electrical elements of the machine; and

Fig. 3 is a diagrammatic representation of the control knob for" the timer, together with a diagr n of the position of the contacts at various mg A washing machine, according to this invention includes a tub 50, which may becentrifugally rotated to dry the clothes. An agitator 5| may.

be placed inside of thetub, for agitating the clothes prior to the centrifugal action. The tub 50 and agitator 5| areactuated through the medium of a transmission 52, which is actuated by a motor 53, the transmission" being controlled by a solenoid 54. When the, motor 53 is energized, together with the solenoid 54, the agitator is not reciprocated; but the tub 50 is centrifugally rotated at sufiicient speed to wring the clothes. When the motor 53 is energizedwhile the solenoid is deenergized, the agitator 5| is reciprocated. When' the solenoid 54 is deenergized while the tub 50 is rotating, a braking action is applied to the tub .50, to stop it quickly. "Any type of motor and transmission may be used for accom: shing is pu ose. uch; f r xampl as is disclosed in the copending application of Kencan Clark, .5. N. 511,515, filed November 24, 1944, Patent No. 2,4223%, granted June 17, 1947,.for Domestic Appliance.

An access door 56 is provided for. introducing the. clothes and detergent into the"tub"50. "A dear switch 51, hinged' at llland'closin'g contacts'at l1, actuated by the rod 58 so that'the'contacts l1 ire closed whenever'the'doo'r 56 is opened, andviceversai .7

'A ime T pacified When-weed the fl w of electrical power. from the lines L1 and L2 to the various electrical elements of the washing machine. The washing machine is filled with w'a'teh'from the hot water connector 60 and a coldwater connector 59. These connectors discharge, into athermo'static, mixin valve 6|. The hot water: connector also discharges into a hot water line ll. The mixing valve 6| discharges into a mixed water line 12"." The lines H and 12 are controlled by solenoid valves 63 and 62 respectively, and d ischarge into a common outlet chamber 55L This chamber is connected by a line 3 'to a constant pressure valve 65, which maintains a constant pressure of water on the line'lfi. which turn discharg'es'through a fixed orifice 66 and anozzle "at a'con'stantfiow rate into the tub 511. "The arrangement is such that the timer 1Q opens the selected solenoid valve 62;"or 63' for. a 'sliiflicient l'er'rgth of time so that the constant volume" discha ge of] water at the nozzle 61 fills the tub 50 to th correct level durmovable contacts 6,

ea fi i g oiie etitm-i Th p si i Of e and 815i he. 'sel tof s t h 88 te ne whether the movable cbntact 89 of the switch 88 contacts 'l5 or 16'. Whenthehandle 8'! is on theindic'ation Hot. contact 89 engages l5, and the hot water solenoid"6 3 is energized for the first filling operationfDur'ihg the second and third filling operations, themiir'ed water solenoid 62 is energized regardless of the position of cona t Fig. 2 shows the timer construction diagrammaticallyi" 'It'inludes'a tini'er motor 20 which niovesa'srnall' gear'Z-l intermittently such as at one-half minute intervals "Ifhis g'ear inturn ac-, tuatesa larger'gear'ZZ, which is fixed to a retatable shaft 23. The shaft 23/ carries a plurality of rotatable earns 24, i5, 25 and 2'! which are 'inengagement with movable blades 28, 29, 311 and 3] respectively, and which carry movable contacts 6, ll, H "and 11 respectively. The cams 24, 25, gs and 21 have been indicated by dotted circles; put it is ui derstood'that they actually are irregularly shaped cams," so shaped that the ll and 8 are actuated at selected intervals of time, as indicated in Fig. 3. Fig, 3shows the indications on the knob 35, which are inside of the circle 135.] The numerals on the outside of circle indicate therpositions of the movable contacts [at the 'various intervals of time," as thesha'ft 23' is rotatdclockwise. Hie kneh provided with ah irregumr orifice 31 which ,fitsiove'r theirreg'u1ar end 38 of the shaft 23, "Ihe knob stisaxiauy secured .to the shaft .1 s that he te 3, s' i d li liil 3 axially, a movable contact 2 is moved into and out of contact with stationary contact I, the movable contact 2 being carried by a movable blade 39 which has its upper end in axial engagement with the shaft 23. Whenever the knob 36 is pulled towards the operator, the contacts I and 2 are opened, and whenever the knob is pushed away from the operator, the contacts I and 2 are closed. A suitable snap acting mechanism is provided for allowing the shaft to be placed in these two axial positions. This may take the form of a double grooved ring 40 carried by the shaft 23 in which a spring-pressed pin 4| rides, so that the ring 40 snaps from one position to the other.

Whenever the movable contact 8 engages contact 9, the solenoid 54 is energized, so that the tub 50 is centriiugally rotated. However, since the switch 51 is closed whenever the door 53 is open, and switch 51 is in parallel with solenoid 54, all electrical elements are automatically deenergized, should the door 56 be open, or opened, during a period which normally is a spin period, as more fully hereinafter explained. Therefore,

should the operator open the door while a centrifugal action i taking place, all operations are automatically stopped, including the operation of the timer. open during any previous operation, then, when the timer reaches a spin position, all operations, including that of the timer, are automatically stopped. The machine then remains inoperative until the operator closes the door 56, at which time the operations of the machine, including the timer, are resumed when they were automatically stopped by the open door.

Also, if the door 56 should be left Normally, when the door 56 is closed and the or 63 (depending on the selection at 89) is en- I ergized to introduce water (hot or tepid) into the tub 50. The electric current flow is from Li, I, 2, I00, 3!, 8, 1, I02, 69 and, if 91 is on hot, I5, I03, 03, I04, I05, I4, I3 to L2. Should the handle 81 be on mix,. -then the current branches from 09 to I6, I06, 52, I01, I05, I4, I3 to L2.

When 8 is on 9 current flows from L1, I, 2, I00, 3i, 0, 9, I08, I09, 54, H0, I05, I4, I3 and L2. This energizes the spin solenoid 54 and causes rota-- tion of tub 50. However, should the door 56 be open, or be opened, while 0 is on 9, then, instead of causing a rotation of tub 50, all operations are stopped by the flow of current from Li, I,

2,. I00, SI, 8, 9, I8, 51, I1, solenoid III, I3 and.

L2. The energization of solenoid III pulls the safety switch I3 from I4. This allows current to continue to flow through solenoid III; but disconnects all other electrical elements, 54, 63, 62, 53 and 20 from L2, thus stopping all operations, including the timer, as long as the door 56 is open and the timer is on a spin position. When the door 56 is closed, switch 51 is opened, and solenoid III is deenergized, thus allowing safety switch contacts I3 and I4 to close on each other by spring action into their normally closed position. It should be noted that this control of the door 56' over the electrical circuits can only take place duringa "spin position of the timer, since that is the only time that contact 8 is on 9, and is the only time that solenoid III can be energized.

When II is on ID (which never occurs'while 8 4 is on 1) tepid water solenoid 62 is energized. Electric current flows from Li, I, 2, H2, 30, II, I0, H3, I06, 62, I01, I05, I4, l3, to L2. The tub 50 is filled with tepid water to the correct level during such an operation.

When II is on l2, the running winding of motor 53 is energized. Electric current flows from L1, I, 2, H2, 30, II, I2, H4, 53, I15, I05, I4, I3, to Le.

When 4 is on 3, the timer motor 20 is energized. Electric current flows from Li, I, 2, H6, H1, 3, 4, 29, H8, 20, I05, I4, I3 to L2.

When 6 is on 5 the starting winding of motor 53 is energized. Electric current flows from Li, I, 2, H6, I19, 5, 6, 28, I20, 53, H5, I05, I4, I3 to L2.

In the operation of the device, the door 55 is opened and clothes and detergent are placed in the tub 50. The door then should be closed and the knob 36 should be pushed away from the user to close contacts I and 2 and the knob 36 should be turned clockwise from the oiT position S (Where the. timer previously had stopped) to the start position at A. Just before reaching position A, the cams are actuated so that contact 3 closes on 4 and contact 1 closes on 8 as indicated at A. This energizes the hot water solenoid and starts the flow of hot or tepid (as selected) water into the tub 50 to the correct level. At the same time the timer motor 20 is energized. The shaft 23, and knob 36 are then intermittently progressed from position A to position 13, where contact 8 is moved away from 1; 5 is moved to 5; and II is moved to I2. This energizes the starting coil of motor 53. It also energizes the running coil of motor 53. The motor 53 is therefore started and caused to run on the starting running windingsthereafter. Since the transmission solenoid 54 is deenergized, the agitator 5I is agitated. After a suitable interval of time, as at C, the starting winding of the motor 53 is deenergized by opening contacts 5 and 6. The washing operation continues (agitator action), for the selected number of minutes, until theposition D isreached. Should the user, desire a shorter washing period than the 10 minutesindicated on the timer, he may advance the knob 36 manually to a shorter period, such as-to an 8, 6 or other minute period. When position D is reached contacts 5 and 6 are closed, as

are 2.1506 and 9.- The closing of contacts 8 and door 56 be opened while the spinning operation progresses or if the door had been left open, then no spinning of the tub can take place, and all operations of the machine, including that of the timer-are interrupted by the opening of contacts I3and I4 as previously described. The spinning operation empties the water in the tub 50-into sump I30 from whence it flows through pipe I3I and pump I32 into drain connector I33.

As the timer continues, the position E is reached where the starting winding is deenergized by the opening of contacts 5 and 6. When the position F .is reached contact 8 is moved from 9 and II from I2. This deenergizes the solenoid 54 and the motor 53 and stops the spinning of tub 50. 1

At position G I0 i s c1osed .on II. This energizes the mixed water solenoid 62 andstarts flow of mixed water through the nozzle 61. The flow of water continues until position H, which :is the correct length of time to fill the tub. At H,.con tact II is moved from In while the contacts 5 and 6, and H and I2 are closed. This stops the fiow of water and energizes the starting and rune, ning windings of the motor 53 to reciprocate :the agitator 5|. At I, contact 6 is moved from 5, thus deenergizing the starting winding of motor 53, the motor 53 continuing to run on the run.- ning winding. From H to J, the agitator 5| is reciprocated. At J contact 6 closes on 5 while contact 8 closes on 9. If the door 56 is closed, the tub 50 starts to spin; but if thedoor is already open, then the tub does not spin and all operations cease until the door is .closed, when they are resumed where they were stopped. At K'the starting winding is deenergized'by the opening of contacts 5 and 6. At L the spinning operation is terminated by the opening of contacts 8 and 9 and II and I2. At M the mixed Water solenoid is opened by the closing of contacts l and H. The filling operation continues until N is reached. The tub has then been filled with tepid water. At N, contacts l0 and II are opened while and 6, and II and i2 are closed. This stops the filling operation and starts the reciprocation of the agitator, the motor 53 running on both its starting andrunning windings. At 0 the starting winding is deenergized by the opening of contacts 5 and 6. At Pthe contacts 5 and 6 are closed as are also contacts 8 and 9. This starts a spinning operation, the motor 53 running on both windings until position Q, when the starting winding is deenergized by theopening of contacts 5 and 6. At R the spinning operation is terminatedby the opening of contacts 18 and 9 and II and I2. It should be noted that, if the door 56 should be opened at any time during the interval between P and R th spinning operation will be stopped together with the timer. If the door has been left open before the reaching of this spinning operation, the basket will not spin and the timer will stop.

After the spinning operation P to R, the timer continues to run until position S is reached when the contacts 3 and 4 are opened, thus deenergizing the timer motor 20. At this time the entire washing operation is terminated and the clothes may be removed from the machine. The knob 36 remains at S until the machine is used again.

The opening of the door 56 does not interfere with any of the filling or agitating operations A to D, F to J, and L to P. However, should the door 56 be open at, or be opened during, the spinning operation, all of the operations of the machine, including the timer operation, are stopped. These operations are resumed upon the closing of the door 56. This allows the user to inspect the interior of the machine at all times except when spinning is taking place. He can even inspect the machine during the spinning operation; but that operation is stopped until the door is closed.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to 'be understood that other forms might be adopted, as may Come within the scope of the claims which follow.

What is claimed is as follows:

1. A washing machine comprising: a centrifugally rotatable basket; agitating means for clothes in said basket; a power motor; transmis sion means to connect said motor to rotate said basket centrifugally and to agitate said clothes;

a liquid ieeder iorisaid basket; a door for access a to said ibasket; .a timer sequentially .to establish whensaiddoor is opened, operable to enable said timer to establish said filling and agitation periods and to disable said timer to establish and continue said spin period; said last named means being (effective to stop said timer if said door is opened during aspin period.

2. A washingmachine comprising: power lines adapted -.to be connected to.a source of power; a rotatable tube; an agitator in said tub; a power motor; atransmission connecting said motorwith said tub and agitator; a spin actuator for said transmission-to cause spinning of said tub; liquid fillingmeans for saidtub; a power motor switch; a timer motor switch; a filling means switch; a spinswitch; a=;timer motor actuating saidswitches at various intervals of time; a normally closed solenoid contactor in series with one power line and all of said switches; the solenoid of said contactor being in serieswith said lineand said spin switch; a door switch'in series with said solenoid and spin switch; and electrical connections from the other power line to the witches, power motor, timer motor, filling means, spin actuator, contactor and solenoid.

3. A washing machine com-prising: power lines adapted to be connected to a source of power; a rotatable tub; an agitator in said tub; a power motor member; a transmission connecting said motor member, tub and'agitator; a spin controller member controlling-saidtransmission to- ,causerotation of said-tub; .a'hot water fill valve member; a tepid water fill valve member; a timer motor member; a movable power motor and tepid water fill blade to control said power motor member and said tepid water fill valve member; a movable timer blade to control said timer motor member; a movable hot water fill and spin blade to control said hot water fill valve member and spin controller member; said timer motor member moving said blades at various intervals of time; stationary contacts for said blades, said last named blade havinga spin stationary contact and a hot water fill contact selectively contactable by said blade; a normally closed solenoid switch in series with one power line and said stationary contacts, the solenoid of said solenoid switch being in series with said one line and with said spin stationary contact; a door switch in series with said solenoid and said spin stationary contact; and electrical connections from the other power line to said member, cer tain of said blades, certain of said contacts, certain of said switches, and said solenoid.

4. A control switch means comprising: a plurality of mechanism control switches; a timer motor sequentially actuating said switches; asafety switch in series with said mechanism control switches and timer; a door; means opening said safety switch when a certain one of said mechanism control switches is actuated and said door is open and closing said safety switch when said certain one of said mechanism control switches is not actuated and said door is either open or closed.

5. A control switch means comprising: a plurality of mechanism control switches; a timer motor sequentially actuating said switches; a

7 safety switch "in 'series'w'ithsaid mechanism control switches and timer; a solenoid controlling :said safety switch, said solenoid being in series with a certain one of said mechanism control ;switches to be electrically modified when said certain switch is actuated and to be electrically unmodified when said certain switch is not actuated.

6. A control switch means comprising: a, plurality of mechanism control switches; a timer motor sequentially actuating said switches; a safety switch in series with said mechanism control switches and timer; a solenoid controlling said safety switch, said solenoid being in series with a certain one of said mechanism control switches to be electrically modified when said certain switch is actuated and to be electrically unmodified when said certain switch is not actuated; and a door controlled switch in series with said solenoid and certain switch.

'7. A control switch means including: a plurality of mechanism control switches; a timer motor switch; a timer motor and cam means drivingly connected to operate said switches to produce sequentially a plurality of mechanical operation periods; a door switch adapted to be operated by a door providing access to said mechanical operations; said door switch, when said door is closed, enabling all of said switches; said door switch, when said door is open, enabling some of said mechanism control switches and said timer motor switch during corresponding mechanical operation periods and disabling another of said mechanism control switches and said timer motor switch during the corresponding mechanical operation period.

8. A control switch means comprising: a plurality of mechanism control switches; a timer motor switch; a timer motor actuating certain of said switches at various intervals of time; a normally closed solenoid contactor in series with one line and said switches; the solenoid of said contactor being in series with said line and a certain one of said mechanism control switches; and a door switch in series with said solenoid and said certain switch.

9. A control switch means comprising: a plurality of mechanism control switch blades; a timer motor moving said blades at various intervals of time; stationary contacts for said blades, a certain one of said blades having a dangerous contact connected with a dangerous mechanism contactable by said blade; a normally closed solenoid switch in series with one line and said stationary contacts, the solenoid of said solenoid switch being in series with said one line and with said dangerous contact; and a door switch operated by a door providing access to said dangerous mechanism in series with said solenoid and said dangerous contact.

HAROLD B. WALLIS. DUANE R. NEAL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Num er Name Date 2,161,604 Watts June 6, 1939 2,176,954 Clark Oct. 24, 1939 2,233,362 Beeman s Feb. 25, 1941 2,302,012 Dyer Nov. 17, 1942 2,302,836 Breckenridge Nov. 24, 1942 2321.641 Anderson June 15, 1943 2,325,663 Claybourne Aug. 3, 1943 2,355,162 Hovey Aug. 8, 1944 

